Brown Pelican Says...

I try to keep my appreciation of nature separate from politics, but sometimes a cause calls. 

If our climate keeps warming at such a rapid pace, the barrier island where I saw this pelican will be underwater. 

Signs of Spring?!

A crocus greeted me when I walked out the side door. Normally, I enjoy seeing crocuses, an early sign of spring. But I am somewhat disturbed by signs of spring the first week of January. 

While watering the potted pansies out back, I noticed green shoots of daffodils poking up through the leaves. Again, I was more dismayed than excited. The daffodils are the Ice Follies variety that bloom in early to mid-spring. Has this winter been so warm that the plants are fooled? It was 70 degrees yesterday.

The neighbors' Japanese quince has begun blooming. 

I hear that the winter in Maine has been so mild that people are still playing golf and snowmobilers are upset by the lack of snow. In Florida at Christmas we experienced near-record warmth, with highs in the low 80s. I didn't complain, but I do wonder. Where is winter?

On December 9, I took this photo of a Prunus mume in bloom at the Coker Arboretum. I haven't had a chance to check back to see if the blooms got nipped when the temperature briefly dipped below freezing, but I have noticed other Japanese apricots in bloom in town.

Could this be another sign of global warming? Yes, I know that we cannot draw firm conclusions from one season of unseasonable weather. But it seems that we've been having many, many seasons of unseasonably warm weather. I trust plants (and my senses) far more than politicians.

Has your winter been unusually mild, too? 

Pledge: One Month Without Driving

My bike was not stolen today while it sat unlocked on the bike rack in back of the hospital where I work. I choose to see this as a good omen concerning bike riding for transportation. (Of course, I am deliberately ignoring alternative explanations: the trustworthiness of passersby, the stodgy appearance of my commuter bike, or the general lack of interest in bike riding.)

I also am reading Barbara Kingsolver’s Animal, Vegetable, Miracle and have been inspired by her description of her family’s year-long experiment in eating only local organic food, much of it grown themselves. Her motivations are the same ones that are driving much of my food choices these days—concern about the vast quantities of fuel used in transporting food, the effect of factory farms on the environment, the tastelessness of most commercial produce, and the unhealthiness of processed food, just to name a few. But much as I love growing plants, I can’t see myself with the stamina (or sunny acres) necessary to grow my own food. I also am going to have to become much more of a cook before I can give up processed food altogether.

What I can emulate is commitment to living according to my principles, although on a much less ambitious scale. Since my number one concern these days is global warming, and most of my carbon footprint is related to driving, I hereby pledge (drum roll, please) I WILL NOT DRIVE FOR ONE MONTH.

I think that giving up driving is feasible, as I live about 1 mile from a grocery store and shopping center and about 3 miles from downtown Chapel Hill. The hardest part will be riding my bike in the heat and humidity of a Southern June, but that is no excuse for one who spent many summers riding bikes and running in the heat of Washington, DC. One caveat: Cookie and I have a long-planned trip to Tennessee for his high school reunion this weekend, so I will have to make an exception for that trip. But I don’t want to use the road trip as an excuse to put off starting to try to live car-free. I will start my experiment tomorrow, May 30, and end it on July 1, so that I have a total of 30 days without driving. Stay tuned for updates on life without driving.

Climate Change in Chapel Hill

Much media attention has been paid in the last year to climate change and some of the more dramatic possible global consequences--sea level rise, drought, and disrupted water supplies, with poor nations bearing much of the burden. But, as a Chapel Hill gardener and frequenter of nature trails, I began to wonder what may happen in my own backyard.

The last 100 years have seen a warming and drying out in piedmont and coastal North Carolina. Temperatures rose significantly in the piedmont and coastal regions, with an increase of 3 degrees F in coastal Carolina between 1911 and 2002, according to a 2006 report by the State Climate Office of North Carolina. Although maximum summer temperatures did not increase significantly in the state in the last century, minimum temperatures rose, particularly in urban areas. As for rainfall, the greatest decrease occurred in Chapel Hill, which saw a decline of 4.1 inches between 1893 and 2002.

Although the International Panel on Climate Change has little to say about global warming’s likely consequences in the Southeastern United States, climate scientists do predict that an increase in temperatures will be accompanied by more frequent storms, more heavy rainfalls, and more frequent droughts.

Flora at the southern end of their distribution range, such as those found in the Appalachian Mountains, will be particularly affected by warming, according to a study by the National Biological Service. Spruces, firs and the rare endemic herbaceous plant, Geum radiatum, are highly vulnerable, says Johnny Randall, assistant director for conservation at the North Carolina Botanical Garden.

Closer to home, Randall says he worries most about Catawba rhododendrons growing on north-facing slopes of Morgan Creek. These rhodies are not particularly well adapted to warmer temperatures and unpredictable rainfall. “I think we’ll see them drop out relatively quickly,” he says.

If plants that like cool conditions may be losers, vines may well be winners in a warming climate. This includes the backyard scourge (and native) poison ivy, Toxicodendron radicans, as well as exotics like Japanese honeysuckle, Lonicera japonica. A study by Duke University found that poison ivy grew 2 ½ times faster with increased carbon dioxide.

A changing climate also favors weedy exotics such as Microstegium vimineum, says Randall. Weeds tend to take over disturbed sites because they are highly adaptable and have a lot of genetic diversity, traits that may give them even more of an edge when some native plants begin to struggle.

Some early shifts in vegetation are already detectable in the Piedmont, as wax myrtle (Myrica cerifera) and Baccharis halimifolia have begun moving inland from the coast, Randall says. It is unclear, however, whether this is related to global warming or to land disturbance created by development, he says.

What’s a gardener to do in these uncertain times? I began to wonder if my neighbor who created a garden entirely of tropicals had the right idea. But Randall helped abolish these heretical thoughts. “Planting native plants is more important than it ever has been if we want to maintain some biodiversity,” Randall says. Biodiversity is an important component of ecosystems’ resilience to change. Another reason to continue using Southeastern native plants in our gardens is that most of them are already are adapted to extremes of weather—heat, periods of drought, and heavy rainfalls.

So, I’m planting a variety of natives, most of them somewhat drought tolerant. I study the heat zone maps and avoid buying plants that are already at the southern end of their comfort zone. I installed a rain barrel to catch runoff from heavy rains and keep my new plants alive during droughts. And, most important, I’m doing what I can to reduce my carbon footprint.